I bet when current management leaves, as usual happens in these cases, those that worship Valve and Steam will see yet another big corporation, this if it doesn't eventually get acquired.
People keep forgetting our time is limited and nothing lasts forever.
It's true that entropy will be the end of us all but while there are definitely things that may end Valve, "management" leaving isn't going to the thing that does it. It might be wise to learn about the company you speak so definitively about, I suggest reading the pamplet.
Nothing lasts forever.